linux-kernel - Re: BUG: selftest/net/tun: Hang in unregister

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 14 Mar 2023 09:02:56 -0700
From:   Eric Dumazet <edumazet@...gle.com>
To:     Mirsad Todorovac <mirsad.todorovac@....unizg.hr>
Cc:     netdev@...r.kernel.org, linux-kselftest@...r.kernel.org,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>, Shuah Khan <shuah@...nel.org>,
        linux-kernel@...r.kernel.org
Subject: Re: BUG: selftest/net/tun: Hang in unregister_netdevice

On Tue, Mar 14, 2023 at 9:01 AM Mirsad Todorovac
<mirsad.todorovac@....unizg.hr> wrote:

> After a while, kernel message start looping:
>
>   kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3
>
> Message from syslogd@...mtodorov at Mar 14 16:57:15 ...
>   kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3
>
> Message from syslogd@...mtodorov at Mar 14 16:57:24 ...
>   kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3
>
> Message from syslogd@...mtodorov at Mar 14 16:57:26 ...
>   kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3
>
> This hangs processes until very late stage of shutdown.
>
> I can confirm that CONFIG_DEBUG_{KOBJECT,KOBJECT_RELEASE}=y were the only changes
> to .config in between builds.
>
> Best regards,
> Mirsad
>

Try adding in your config

CONFIG_NET_DEV_REFCNT_TRACKER=y
CONFIG_NET_NS_REFCNT_TRACKER=y

Thanks.